AvinashK's questions

I am using Ubuntu 12.04. I wrote a simple hello world kernel module (hello.c). I wrote the folllowing makefile for it:

obj-m+=hello.o
KDIR:= /usr/src/linux-headers-3.2.0-24-generic-pae
all:
     $(MAKE) -C $(KDIR) SUBDIRS=$(PWD) modules
clean:
     rm -rf *.o *.ko *.mod.* *.symvers *.order 

But this error cropped up when I did make from kernel:

make[1]: Entering directory `/usr/src/linux-headers-3.2.0-24-generic-pae'
make[2]: *** No rule to make target `arch/x86/tools/relocs.c', needed
by `arch/x86/tools/relocs'.  Stop.

hello.c and makefile are in /Documents/module_prog. I ran make from that directory.

What is causing this error and how can I fix it?

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I was trying to install postfix on Ubuntu 11.10 for SMTP support... I typed

sudo apt-get install postfix

and then the installation started.

But during installation a configuration screen popped up which requested me to select an option. Now the problem is that there is no link to accept an option in the configuration screen, and as I can't select an option the installation process stalls.

If i exit the terminal and again try to re-install i get a message

could not get lock /var/cache/apt/archives/lock -open(11. resource temporarily    unavailable)

Screenshots of the problem: